如何在条形图中的amchart4中显示工具提示

Question

categoryAxis.renderer.labels.template.tooltip =新的am4core.Tooltip（）;

        categoryAxis.renderer.labels.template.tooltip.setBounds({ x: 0, y: 0, width: 20000, height: 20000 }); // for the tooltip not to go out of bounds

        categoryAxis.renderer.labels.template.tooltip.pointerOrientation = "vertical";

        categoryAxis.renderer.labels.template.cloneTooltip = false; 
        // this is important. otherwise a separate tooltip for each label will be created, which is not good for performance

        // // Enable axis tooltip in general

        categoryAxis.renderer.labels.template.adapter.add("tooltipText", function (text,event) {
            if (text && text.length <= categoryCharacterLimit) {
                return "";
            }

             categoryAxis.renderer.labels.template.tooltipText = "{category}";
        });